This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 45 |
| 4 | 201 |
| 5 | 819 |
| 6 | 3231 |
| 7 | 12321 |
| 8 | 46209 |
| 9 | 170370 |
| 10 | 621316 |
| 11 | 2240838 |
| 12 | 8011584 |
| 13 | 28395213 |
| 14 | 99845553 |
| 15 | 348333411 |
| 16 | 1205925033 |
| 17 | 4142850423 |